I've always wanted to make the Space Shuttle for FlightGear, and recently, I just explored some sides of JSBSim I haven't looked at before, so I've planned out the launch sequence, boosters, ext. tanks and stuff. It's still very difficult finding system information on the Space Shuttles. I'm not promising that I'll do anything now, but I will try if I have time after the ATR72-500(C) I'm working on.
Cheers!